deepseek-ai/deepseek-harness · error · RequestError

-32602

-32602

Error message

unknown session: ${sessionId}

What it means

Error "unknown session: ${sessionId}" thrown in deepseek-ai/deepseek-harness.

Source

Thrown at packages/acp/acp/src/index.ts:143

  const logger = ctx.logger
  const sessions = new Map<SessionId, SessionRecord>()
  let closed = false
  let conn: AgentSideConnection
  let imagePromptEnabled = false

  /** Return the bridge-owned record for an agent, rejecting same-id impostors. */
  const ownedRecord = (agent: Agent): SessionRecord | undefined => {
    const record = sessions.get(agent.session.id)
    return record?.agent === agent ? record : undefined
  }

  const assertOpen = (): void => {
    if (closed) throw internalError('the ACP bridge has been disposed')
  }

  const requireSession = (sessionId: SessionId): SessionRecord => {
    const record = sessions.get(sessionId)
    if (record === undefined) throw invalidParams(`unknown session: ${sessionId}`)
    return record
  }

  /** Send one ordered protocol update while containing transport-only failure. */
  const notify = async (notification: SessionNotification): Promise<void> => {
    try {
      await conn.sessionUpdate(notification)
    /* v8 ignore start -- the ACP SDK contains notification-handler failures; only a transport write failure reaches this guard. */
    } catch (error: unknown) {
      logger.warn(`acp: session/update failed: ${String(error)}`)
    }
    /* v8 ignore stop */
  }

  const rejectFromError = (
    inflight: NonNullable<SessionRecord['inflight']>,
    reason: Extract<TurnEndReason, { kind: 'error' }>,
  ): void => {

View on GitHub (pinned to b150a551b8)

Solutions

1. Use a valid existing sessionId or create a new session before sending the request.

When it happens

Trigger: Thrown at packages/acp/acp/src/index.ts:143 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of deepseek-ai/deepseek-harness@b150a551b8 (2026-08-24). Data as JSON: /api/errors/80c9a8fc0193804f. Report an issue: GitHub.